The present invention relates to an air compressor, and particularly relates to an air compressor that is mounted on a tank.
An air compressor may be used to provide a hand-held tool with pneumatic power. The compressor is part of an apparatus that further includes a motor for driving the compressor and a tank for storing compressed air. A drive assembly operatively interconnects the motor with the compressor, and is mounted on the tank with the motor and the compressor. The drive assembly may include a pulley, a flywheel, and a linkage structure that cooperate to reciprocate a piston within the compressor upon rotation of an output shaft at the motor. The reciprocating piston pumps compressed air into the tank. A pneumatic power hose extends from the tank to the pneumatically powered tool. In some cases the tank is provided with wheels and a handle so that the entire apparatus is portable.
In accordance with the present invention, an apparatus includes an air compressor, a motor, and a drive assembly operatively interconnecting the motor with the compressor. The compressor contains a piston in a cylinder. The motor has an output shaft. The drive assembly includes a flywheel and a bearing that supports the flywheel for rotation about an axis. A drive belt transmits torque from the output shaft to the flywheel so as to rotate the flywheel upon rotation of the output shaft. A linkage structure interconnects the flywheel with the piston so as to reciprocate the piston in the cylinder upon rotation of the flywheel.
The drive assembly further includes a shaft extending along the axis between the flywheel and the bearing. A first end portion of the shaft is journaled in the bearing for rotation about the axis. A second end portion of the shaft is received within a bore in the flywheel with an interference fit between an outer surface of the shaft and an inner surface of the flywheel.
In a preferred embodiment of the invention, the flywheel is a cast metal part and is free of a machined finish at the inner surface. The inner and outer surfaces of the flywheel and the shaft have complementary tapered contours, and are tapered radially inward in a direction extending axially from the flywheel toward the bearing. The shaft in the preferred embodiment further engages an inner race of the bearing with an interference fit between the outer surface of the shaft and an inner surface of the race.